Influence of water in the reaction of gamma-aminopropyltriethoxysilane with silica-gel - a fourier-transform infrared and cross-polarization magic-angle-spinning nuclear-magnetic-resonance study
Vrancken, Kc × Vandervoort, P Gillisdhamers, I Vansant, Ef Grobet, Pierre #
Royal soc chemistry
Journal of the chemical society-faraday transactions vol:88 issue:21 pages:3197-3200
Silica gel has been modified with gamma-aminopropyltriethoxysilane under varying conditions, controlling the influence of water in the different modification stages, Diffuse reflectance infrared Fourier-transform (DRIFT) spectra revealed the influence of surface water in the reaction stage and of air humidity in the curing stage. These results were confirmed and refined by Si-29 and C-13 cross-polarisation magic-angle-spinning nuclear magnetic resonance (CPMASNMR) spectroscopy. Combining the results of both techniques, four modification structures present on the silica surface are proposed, depending on the conditions used.